321 research outputs found
Correlated Prompt Fission Data in Transport Simulations
Detailed information on the fission process can be inferred from the
observation, modeling and theoretical understanding of prompt fission neutron
and -ray~observables. Beyond simple average quantities, the study of
distributions and correlations in prompt data, e.g., multiplicity-dependent
neutron and \gray~spectra, angular distributions of the emitted particles,
-, -, and -~correlations, can place stringent
constraints on fission models and parameters that would otherwise be free to be
tuned separately to represent individual fission observables. The FREYA~and
CGMF~codes have been developed to follow the sequential emissions of prompt
neutrons and -rays~from the initial excited fission fragments produced
right after scission. Both codes implement Monte Carlo techniques to sample
initial fission fragment configurations in mass, charge and kinetic energy and
sample probabilities of neutron and ~emission at each stage of the
decay. This approach naturally leads to using simple but powerful statistical
techniques to infer distributions and correlations among many observables and
model parameters. The comparison of model calculations with experimental data
provides a rich arena for testing various nuclear physics models such as those
related to the nuclear structure and level densities of neutron-rich nuclei,
the -ray~strength functions of dipole and quadrupole transitions, the
mechanism for dividing the excitation energy between the two nascent fragments
near scission, and the mechanisms behind the production of angular momentum in
the fragments, etc. Beyond the obvious interest from a fundamental physics
point of view, such studies are also important for addressing data needs in
various nuclear applications. (See text for full abstract.)Comment: 39 pages, 57 figure files, published in Eur. Phys. J. A, reference
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Report of CE on Semantic DS
ISO/IEC JTC1/SC29/WG11, MPEG00/M6355, 53rd meeting, Jul. 2000, Beijing, PR
High Burnup Effects Program A State-of-the-Technology Assessment
Various analytical models and empirical correlations describing the fission gas release phenomenon were examined. An evaluation was made of the current pertinent experimental data on the subject of high burnup fission gas release. Data reported by individual investigators were compared and evaluated in relation to their applicability to the content and scope of the High Burnup Effects Program. These evaluations then form the bases for defining the data needs, and the selection of variables to be studied in this program
Immunological changes in nestlings growing under predation risk
Predation is one of the most relevant selective forces in nature. However, the physiological mechanisms behind anti-predator strategies have been overlooked, despite their importance to understand predator-prey interactions. In this context, the immune system could be especially revealing due to its relationship with other critical functions and its ability to enhance prey's probabilities of survival to a predator's attack. Developing organisms (e.g. nestlings) are excellent models to study this topic because they suffer a high predation pressure while undergoing the majority of their development, which maximizes potential trade-offs between immunity and other biological functions. Using common blackbirds Turdus merula as model species, we experimentally investigated whether an elevated nest predation risk during the nestling period affects nestlings' immunity and its possible interactions with developmental conditions (i.e. body condition and growth). Experimental nestlings modified some components of their immunity, but only when considering body condition and growth rate, indicating a multifaceted immunological response to predation risk and an important mediator role of nestlings' developmental conditions. Predation risk induced a suppression of IgY but an increase in lymphocytes in nestlings with poor body condition. In addition, experimental but not control nestlings showed a negative correlation between growth and heterophils, demonstrating that nest predation risk can affect the interaction between growth and immunity. This study highlights the importance of immunity in anti-predator response in nestlings and shows the relevance of including physiological components to the study of predation risk.</p
Work-Unit Absenteeism: Effects of Satisfaction, Commitment, Labor Market Conditions, and Time
Prior research is limited in explaining absenteeism at the unit level and over time. We developed and tested a model of unit-level absenteeism using five waves of data collected over six years from 115 work units in a large state agency. Unit-level job satisfaction, organizational commitment, and local unemployment were modeled as time-varying predictors of absenteeism. Shared satisfaction and commitment interacted in predicting absenteeism but were not related to the rate of change in absenteeism over time. Unit-level satisfaction and commitment were more strongly related to absenteeism when units were located in areas with plentiful job alternatives
Conservation of a pH-sensitive structure in the C-terminal region of spider silk extends across the entire silk gene family
Spiders produce multiple silks with different physical properties that allow them to occupy a diverse range of ecological niches, including the underwater environment. Despite this functional diversity, past molecular analyses show a high degree of amino acid sequence similarity between C-terminal regions of silk genes that appear to be independent of the physical properties of the resulting silks; instead, this domain is crucial to the formation of silk fibres. Here we present an analysis of the C-terminal domain of all known types of spider silk and include silk sequences from the spider Argyroneta aquatica, which spins the majority of its silk underwater. Our work indicates that spiders have retained a highly conserved mechanism of silk assembly, despite the extraordinary diversification of species, silk types and applications of silk over 350 million years. Sequence analysis of the silk C-terminal domain across the entire gene family shows the conservation of two uncommon amino acids that are implicated in the formation of a salt bridge, a functional bond essential to protein assembly. This conservation extends to the novel sequences isolated from A. aquatica. This finding is relevant to research regarding the artificial synthesis of spider silk, suggesting that synthesis of all silk types will be possible using a single process
I had no other choice but to catch it too : the roles of family history and experiences with diabetes in illness representations.
BACKGROUND: A family history of diabetes and family members\u27 experiences with diabetes may influence individuals\u27 beliefs and expectations about their own diabetes. No qualitative studies have explored the relationship between family history and experiences and individuals\u27 diabetes illness representations.
METHODS: Secondary data analysis of 89 exploratory, semi-structured interviews with adults with type 1 or type 2 diabetes seeking care in an urban health system. Participants had a recent diabetes-related ED visit/hospitalization or hemoglobin A1c \u3e 7.5%. Interviews were conducted until thematic saturation was achieved. Demographic data were collected via self-report and electronic medical record review. Interviews were audio-recorded, transcribed, and coded using a conventional content analysis approach. References to family history and family members\u27 experiences with diabetes were analyzed using selected domains of Leventhal\u27s Common Sense Model of Self-Regulation.
RESULTS: Participants cited both genetic and behavioral family history as a major cause of their diabetes. Stories of relatives\u27 diabetes complications and death figured prominently in their discussion of consequences; however, participants felt controllability over diabetes through diet, physical activity, and other self-care behaviors.
CONCLUSIONS: Findings supported an important role of family diabetes history and experience in development of diabetes illness representations. Further research is needed to expand our understanding of the relationships between these perceptions, self-management behaviors, and outcomes. Family practice providers, diabetes educators and other team members should consider expanding assessment of current family structure and support to also include an exploration of family history with diabetes, including which family members had diabetes, their self-care behaviors, and their outcomes, and how this history fits into the patient\u27s illness representations
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Maternal satisfaction with group care: a systematic review
OBJECTIVE
This review examined the quantitative relationship between group care and overall maternal satisfaction compared with standard individual care.
DATA SOURCES
We searched CINAHL, Clinical Trials, The Cochrane Library, PubMed, Scopus, and Web of Science databases from the beginning of 2003 through June 2023.
STUDY ELIGIBILITY CRITERIA
We included studies that reported the association between overall maternal satisfaction and centering-based perinatal care where the control group was standard individual care. We included randomized and observational designs.
METHODS
Screening and independent data extraction were carried out by 4 researchers. We extracted data on study characteristics, population, design, intervention characteristics, satisfaction measurement, and outcome. Quality assessment was performed using the Cochrane tools for Clinical Trials (RoB2) and observational studies (ROBINS-I). We summarized the study, intervention, and satisfaction measurement characteristics. We presented the effect estimates of each study descriptively using a forest plot without performing an overall meta-analysis. Meta-analysis could not be performed because of variations in study designs and methods used to measure satisfaction. We presented studies reporting mean values and odds ratios in 2 separate plots. The presentation of studies in forest plots was organized by type of study design.
RESULTS
A total of 7685 women participated in the studies included in the review. We found that most studies (ie, 17/20) report higher satisfaction with group care than standard individual care. Some of the noted results are lower satisfaction with group care in both studies in Sweden and 1 of the 2 studies from Canada. Higher satisfaction was present in 14 of 15 studies reporting CenteringPregnancy, Group Antenatal Care (1 study), and Adapted CenteringPregnancy (1 study). Although indicative of higher maternal satisfaction, the results are often based on statistically insignificant effect estimates with wide confidence intervals derived from small sample sizes.
CONCLUSION
The evidence confirms higher maternal satisfaction with group care than with standard care. This likely reflects group care methodology, which combines clinical assessment, facilitated health promotion discussion, and community-building opportunities. This evidence will be helpful for the implementation of group care globally
Development of the Uncertainty Communication Checklist: A Patient-Centered Approach to Patient Discharge From the Emergency Department
Clear communication with patients upon emergency department (ED) discharge is important for patient safety during the transition to outpatient care. Over one-third of patients are discharged from the ED with diagnostic uncertainty, yet there is no established approach for effective discharge communication in this scenario. From 2017 to 2019, the authors developed the Uncertainty Communication Checklist for use in simulation-based training and assessment of emergency physician communication skills when discharging patients with diagnostic uncertainty. This development process followed the established 12-step Checklist Development Checklist framework and integrated patient feedback into 6 of the 12 steps. Patient input was included as it has potential to improve patient-centeredness of checklists related to assessment of clinical performance. Focus group patient participants from 2 clinical sites were included: Thomas Jefferson University Hospital, Philadelphia, PA, and Northwestern University Hospital, Chicago, Illinois. The authors developed a preliminary instrument based on existing checklists, clinical experience, literature review, and input from an expert panel comprising health care professionals and patient advocates. They then refined the instrument based on feedback from 2 waves of patient focus groups, resulting in a final 21-item checklist. The checklist items assess if uncertainty was addressed in each step of the discharge communication, including the following major categories: introduction, test results/ED summary, no/uncertain diagnosis, next steps/follow-up, home care, reasons to return, and general communication skills. Patient input influenced both what items were included and the wording of items in the final checklist. This patient-centered, systematic approach to checklist development is built upon the rigor of the Checklist Development Checklist and provides an illustration of how to integrate patient feedback into the design of assessment tools when appropriate
Simulation-based mastery learning compared to standard education for discussing diagnostic uncertainty with patients in the emergency department: a randomized controlled trial.
BACKGROUND: Diagnostic uncertainty occurs frequently in emergency medical care, with more than one-third of patients leaving the emergency department (ED) without a clear diagnosis. Despite this frequency, ED providers are not adequately trained on how to discuss diagnostic uncertainty with these patients, who often leave the ED confused and concerned. To address this training need, we developed the Uncertainty Communication Education Module (UCEM) to teach physicians how to discuss diagnostic uncertainty. The purpose of the study is to evaluate the effectiveness of the UCEM in improving physician communications.
METHODS: The trial is a multicenter, two-arm randomized controlled trial designed to teach communication skills using simulation-based mastery learning (SBML). Resident emergency physicians from two training programs will be randomly assigned to immediate or delayed receipt of the two-part UCEM intervention after completing a baseline standardized patient encounter. The two UCEM components are: 1) a web-based interactive module, and 2) a smart-phone-based game. Both formats teach and reinforce communication skills for patient cases involving diagnostic uncertainty. Following baseline testing, participants in the immediate intervention arm will complete a remote deliberate practice session via a video platform and subsequently return for a second study visit to assess if they have achieved mastery. Participants in the delayed intervention arm will receive access to UCEM and remote deliberate practice after the second study visit. The primary outcome of interest is the proportion of residents in the immediate intervention arm who achieve mastery at the second study visit.
DISCUSSION: Patients\u27 understanding of the care they received has implications for care quality, safety, and patient satisfaction, especially when they are discharged without a definitive diagnosis. Developing a patient-centered diagnostic uncertainty communication strategy will improve safety of acute care discharges. Although use of SBML is a resource intensive educational approach, this trial has been deliberately designed to have a low-resource, scalable intervention that would allow for widespread dissemination and uptake.
TRIAL REGISTRATION: The trial was registered at clinicaltrials.gov (NCT04021771). Registration date: July 16, 2019
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